import $ from 'jquery';

$(function(){
    var show_num = [];
    draw(show_num);
    $("#canvas").on('click',function(){
     draw(show_num);
    })
    $(".login").on('click',function(){
     var val = $(".verCode").val().toLowerCase();
     var num = show_num.join("");
     if(val==''){
      alert('请输入验证码！');
     }else if(val == num){
      alert('提交成功！');
      $(".verCode").val('');
      // draw(show_num);
     }else{
      alert('验证码错误！请重新输入！');
      $(".verCode").val('');
      // draw(show_num);
     }
    })
   })
   //生成并渲染出验证码图形
   function draw(show_num) {
    var canvas_width=$('#canvas').width();
    var canvas_height=$('#canvas').height();
    var canvas = document.getElementById("canvas");//获取到canvas的对象，演员
    var context = canvas.getContext("2d");//获取到canvas画图的环境，演员表演的舞台
    canvas.width = canvas_width;
    canvas.height = canvas_height;
    var sCode = "a,b,c,d,e,f,g,h,i,j,k,m,n,p,q,r,s,t,u,v,w,x,y,z,A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0";
    var aCode = sCode.split(",");
    var aLength = aCode.length;//获取到数组的长度
    for (var i = 0; i < 4; i++) { //这里的for循环可以控制验证码位数（如果想显示6位数，4改成6即可）
     var j = Math.floor(Math.random() * aLength);//获取到随机的索引值
     // var deg = Math.random() * 30 * Math.PI / 180;//产生0~30之间的随机弧度
     var deg = Math.random() - 0.5; //产生一个随机弧度
     var txt = aCode[j];//得到随机的一个内容
     show_num[i] = txt.toLowerCase();
     var x = 10 + i * 20;//文字在canvas上的x坐标
     var y = 20 + Math.random() * 8;//文字在canvas上的y坐标
     context.font = "bold 23px 微软雅黑";
     context.translate(x, y);
     context.rotate(deg);
     context.fillStyle = randomColor();
     context.fillText(txt, 0, 0);
     context.rotate(-deg);
     context.translate(-x, -y);
    }
    for (var i = 0; i <= 5; i++) { //验证码上显示线条
     context.strokeStyle = randomColor();
     context.beginPath();
     context.moveTo(Math.random() * canvas_width, Math.random() * canvas_height);
     context.lineTo(Math.random() * canvas_width, Math.random() * canvas_height);
     context.stroke();
    }
    for (var i = 0; i <= 30; i++) { //验证码上显示小点
     context.strokeStyle = randomColor();
     context.beginPath();
     var x = Math.random() * canvas_width;
     var y = Math.random() * canvas_height;
     context.moveTo(x, y);
     context.lineTo(x + 1, y + 1);
     context.stroke();
    }
   }
   //得到随机的颜色值
   function randomColor() {
    var r = Math.floor(Math.random() * 256);
    var g = Math.floor(Math.random() * 256);
    var b = Math.floor(Math.random() * 256);
    return "rgb(" + r + "," + g + "," + b + ")";
   }